Dynamic variable fuel optimization system

ABSTRACT

Present invention optimizes utilization of different fuels in various single and multi-fueled engines. The fuel system and optimization controller links fuel properties (physical, reactionary, combustion etc.) to on-board computer systems during the refueling process. This link enables fuel and additive producers an opportunity to optimize combustion parameters of their proprietary fuel blends to increase performance, fuel efficiencies and reduce emissions.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a Continuation In Part Application of InternationalApplication Serial No. PCT/US2013/040944 titled Dynamic Variable FuelOptimization System, filed May 14, 2013, claiming priority of U.S.Provisional Application Ser. No. 61/646,423 titled Dynamic Variable FuelOptimization System, filed May 14, 2012. In addition, this applicationis supplemented by and claims priority of U.S. Provisional PatentApplication No. 61/903,605, titled Dynamic Variable Fuel OptimizationSystem, filed Nov. 13, 2013, each herein incorporated by reference.

FIELD OF THE INVENTION

The present invention is related generally to the field of vehicle fueloptimization, and in particular to a system to adjust engine operationconditions based on fuel grade properties of the fuel dispensed in thevehicle's fuel tank and a system to enable use and blend traditional andalternative fuels during the operation of a vehicle.

BACKGROUND OF THE INVENTION

Current renewable fuels and fuel systems only enable the user to operateon a single biofuel/biofuel blend. Biodiesel, biofuel, renewable fuel,etc., are all used interchangeably as it relates to system descriptionsand operation. Below are two examples of current systems.

Example A: The user has a stock vehicle with a single draw tankscenario. The user fills the tank with commercially available biodiesel.This biodiesel is what is available at the pump and the user has noinput in this selection. In September the user fills the tank with B20(a 20% blend of biodiesel 80% diesel) in a location where during the daythe temperature averages high 60's low 70's, and at night thetemperature drops into the 40's. The biodiesel fuel will begin to gel asthe temperature drops. This will cause hard starts and filter cloggingin the vehicle. Because this vehicle is only operating on the originalequipment manufacturer's or stock fuel system, the user's vehicle wouldbe rendered inoperable until the fuel warmed up or maintenance wasperformed.

Example B: The user has what is currently available as a renewable fuelsystem added to the stock fuel system configuration. This enables theuser to operate on pure (100%) concentrations of renewable fuel becausethe renewable fuel system operates in auxiliary to the stock system.Traditional operation would be as follows: The user fills the vehicle'sstock tank with diesel fuel and the auxiliary tank with 100% biodiesel.The engine starts and shuts down on the traditional diesel fuel systemand this alleviates the issues associated with cold weather performance.As the engine warms up on diesel, the alternative fuel system is beingheated. When the biofuel is sufficiently heated, the system switchesover to the 100% biodiesel tank either manually or automaticallydepending on the system. Primarily, the fuel system components areisolated from one another so that the diesel and renewable fuel systemsoperate independently and do not cross contaminate. This scenario allowsthe user to operate on diesel or renewable fuel in an “either or”situation. The vehicle is either running on diesel or renewable fuel.

Both of these examples have significant drawbacks. A fixed fuel scenariois not ideal in most operations but it is the only available solution,and therefore standard operating procedure.

Currently, there are no automatic engine parameter adjustment systemsthat determine and set the optimal engine operating conditions based onspecific fuel characteristics of the fuel being utilized. The commercialmarket is any and all combustion engines that preferably operate withsome type of electronic fuel system controls. In practice, the mostbeneficial applications are for large volume fuel users. Some users arelarge heavy equipment and fleet operators that could see a significantreturn from these efficiency increases. For example, a user paying$4.00/gal and utilizing 25,000 gallons of fuel annually that can realizean efficiency increase of 5% by utilizing a system that optimizes fuelutilization, which is a savings of 1,250 gallons of fuel or roughly$5,000 annually. In a scenario where the fuel optimization system isbeing utilized to implement an alternative fuel at an estimated savingsof $.50 per gallon, the cost savings annually could be $12,500 coupledwith the 5% efficiency increase, the client has the potential to realizea savings of up $17,500 annually per truck. In a fleet of 100 trucks,this savings could be almost $2,000,000 annually.

Outside of the actual fuel user, the fuel producer has a significantincentive for implementation of an optimal fuel utilization system. If afleet has a choice between Fuel A and Fuel B, where Fuel B has beencharacterized and is compatible with the fuel optimization system andcan provide a 5% efficiency gain over Fuel A; the fleet has a muchgreater incentive to utilize Fuel B. This gives the Fuel Producer B acompetitive edge over Fuel Producer A and locks in a long-term customer.If fuel producers are creating proprietary fuels, additives, etc. andcan enhance the combustion of these by utilizing a fuel optimizationsystem—competition is created between the producers to improve theperformance of their fuels/additives and they have an incentive toimplement fuel optimization systems to acquire additional clients.

SUMMARY OF THE INVENTION

The present invention is adaptable to a renewable fuel system that canautomatically or manually configure a vehicle's fuel system parametersto operate on a blend of traditional/alternative fuel ranging from0-100%, where 0% blend is 100% traditional diesel and 100% blend is 100%alternative fuel.

The present invention optimizes utilization of petroleum or bio derivedfuels in various single and multi-fueled engines. The present inventioncan include a retrofit device to an external fuel dispensing systemcapable of real-time communication of fuel properties (physical,reactionary, combustion etc.) to on-board computer systems during therefueling process. The on-board computer system of the present inventioncan interface with the Original Equipment Manufacturer's electroniccontrol units (if present) to adjust engine operating conditions tooptimize combustion parameters of the dispensed fuel blends to increaseperformance, fuel efficiencies and reduce emissions.

As mentioned above, the present invention supports use of an auxiliaryrenewable fuel system for combustion engines by enabling engineoptimization when liquid fuels from bio-mass are used. The presentinvention is designed to enable usage of high concentration blends ofbiofuel while achieving optimal emission and performance results fromthe engine. The system can be an auxiliary system retrofit to the stockfuel system or an integrated solution installed by the OriginalEquipment Manufacturer (OEM). The present invention is designed to workwith a variety of fuels and is intended to be fuel neutral. Potentialalternative fuels include, but are not limited to, Biodiesel, VegetableOil, Animal Fats, Plant Oils, Ethanol and CNG for use in bothcompression ignition and spark ignition engines. The system is alsoapplicable for any type of traditional fuel such as gasoline and dieseland additives to any such type of fuel.

One embodiment of the present invention does not require the addition ofadditives or substances to the fuel utilized to change the fuelproperties, for example heating and cooling are utilized to adjust theviscosity of the alternative fuel.

For a better understanding of the present invention, together with otherand further objects thereof, reference is made to the accompanyingdrawings and detailed description.

BRIEF DESCRIPTION OF THE DRAWINGS

The present invention is illustratively shown and described in referenceto the accompanying drawings, in which:

FIG. 1 is an exemplary illustration of a database storing fuelcombustion maps of the present invention;

FIG. 1A is an exemplary illustration of comprehensive fuelcharacterization tables of the present invention and a database storingsuch tables;

FIG. 2 is an illustration of the refueling process and system of thepresent invention;

FIG. 3 is a logic flow diagram of the refueling operation interfacingwith compatible and non-compatible fuel dispensing systems;

FIG. 4 is a further detailed flow diagram of refueling operation of thepresent invention;

FIG. 5 is a pictorial illustrate of an example of adding 75% by volumeFuel B to a tank containing 25% by volume Fuel A;

FIG. 6 is an exemplary system diagram of various examples of thecapabilities of the electronic controls technology of the presentinvention;

FIG. 7 is a schematic of one embodiment of the present inventioncomprised of internal and external communication networks to performfuel system optimization of integrated OEM fuel system components asintegrated with one embodiment of renewable fuel system retrofitcomponents;

FIG. 8 is a diagram that shows the present invention's utilization offuel properties to optimize driver performance through real-timefeedback;

FIG. 9 is schematic logic flow diagram of how the present inventionoperates during a regeneration cycle in the instance that a dieselparticulate filter is installed on an engine which has a renewable fuelsystem installed;

FIG. 10. is a diagram of a fuel tank with one embodiment of an onboardadditive mixing system retrofit components installed;

FIG. 11. is a diagram that identifies one method for how the presentinvention utilizes fuel emission maps track and aggregate engineemission reductions;

FIG. 12. is one example of how a fuel combustion map is determined basedupon a linear correlation of fuel properties.

FIG. 13. is an example of a viscosity blend curve at one temperature ina fuel blend map for a diesel/B100 (100% biodiesel) fuel blend;

FIG. 14. is an example of a viscosity blend curve at one temperature ina fuel blend map for a diesel/WVO (waste vegetable oil) fuel blend; and

FIG. 15 is an example of a biofuel time vs. engine RPM plot/

DETAILED DESCRIPTION OF THE INVENTION

As used herein in the specification and claims, including as used in theexamples and unless otherwise expressly specified, all numbers may beread as if prefaced by the word “about”, even if the term does notexpressly appear. Also, any numerical range recited herein is intendedto include all sub-ranges subsumed therein. The present invention willbe described herein as a total integrated fuel injection control systeminstalled by the Original Equipment Manufacturer. However, one skilledin the art will appreciate and recognize that certain components andsub-systems are standard equipment on current commercial vehicles,whereas other components and sub-systems are unique to the presentinvention and can be added or retro-fitted to cooperate with theexisting fuel injection system of current commercial vehicles.

Now turning to FIG. 1, the present invention 2 is adaptable to usevarious types of fuels where the characteristics of the fuel arerepresented as data in combustion fuel maps 12,18,24 stored in aCombustion Fuel Map Database 10. The example in FIG. 1 illustrates threetypes of fuel, though the present invention is not to be limited to anyspecific number of fuel maps: Fuel A with additives 1, 2, 3 (12) havingcombustion characteristics 1 (14) and 2 (16); Fuel A with no additives(18) having combustion characteristics 3 (20) and 4 (22); and Fuel Bwith additives 1, 2, 3 (24) having combustion characteristics 5 (26) and6 (28). During refueling, the on-board Optimizing Electronic ControlUnit (ECU) 32 (see FIG. 2) receives comprehensive fuel characterizationdata from the fuel dispensing system 30 by downloading the ComprehensiveFuel Characterization Table (see FIG. 1A) best suited for the particularfuel and particular engine model. One skilled in the art will recognizethat each different type of engine may have unique fuel combustion mapsand fuel emissions profiles for each fuel type. The comprehensive fuelcharacterization tables 210 utilize combustion maps 12,18,24 to adjustengine timing, injection cycles, exhaust gas re-circulation (EGR), andother critical engine operational characteristics in combination withthe appropriate fuel system pressures, operational guidelines (start-upoffsets on diesel fuel) and fuel blend maps 212, 214, 216 to adjustoptimal fuel blends and performance of the renewable fuel system 156(see FIG. 7) as determined by on-board Optimizing ECU 32 fromcomprehensive fuel characterization data received from the fueldispensing system 30.

Now turning to FIG. 5, an example of a fuel type that could be optimizedby the present invention is compressed natural gas 62. Natural gas isfueled from a compressor-style fueling station, such as fuel dispensingsystem 30 shown in FIG. 2. These stations are supplied natural gas fromthe utility grid; generally speaking, natural gas is constant. There arehowever variations in the gas properties that can impact performance andcombustion that present invention 2 can accommodate for. The presentinvention 2 also enables the supplier to blend an additive into the gasas it is being fueled into the vehicle and adjust the performance of theengine based on the combustion property variations of the combustionfuel maps, such as Fuel A (12) and Fuel B (24), shown in FIG. 1. Thevehicle equipped with the present invention 2 will load thecorresponding comprehensive fuel characterization table 210 withcombustion fuel maps 12, 18, 24 having fuel characteristics 14, 16, 20,22, 26, and 28 to ensure the maximum performance is derived from theseadditional additives (discussed in detail below).

Now returning to FIG. 2 for an overview of the present invention 2. Oneembodiment of the present invention 2 includes a fuel characterizationtable retrofit device 40 to fuel dispensing system 30 that communicateswith vehicle on-board Optimizing ECU 32 of the present invention 2 toidentify the comprehensive fuel characterization table 210 (for exampleincluding fuel combustion maps 12, 18, 24 and fuel blend maps 212, 214,216 FIG. 1 and FIG. 1A) of the fuel being pumped into a single tank ormultiple tanks 110, 112 of vehicle 38. On-board ECU 32 is an embeddedsystem (or microcontroller) that controls, automates and optimizes theOEM fuel system and or renewable fuel system retrofit 156 (see FIG. 7).When a fuel distributor 42 delivers fuel to a fuel dispensing system 30,information such as the comprehensive fuel characterization table 210along with the amount of fuel dispensed into the station supply orstorage tank 44 is transmitted to fuel dispensing system 30. The fuelcombustion maps 12,18,24 with operational characteristics for particularfuels are downloaded from the fuel characterization table retrofitdevice 40 to fuel dispensing system 30. A retrofit device located onnozzle 46 initiates the communication between the fuel characterizationtable retrofit device 40 unit of the fuel dispensing system 30 and theon-board electronic control unit (ECU) 32 to download, for example, thefuel combustion maps 12, 18, 24 having characteristics 14, 16, 20, 22,26, and 28 to the on-board ECU 32 via connection 176, as well asdownloading the quantity of fuel that was dispensed into tanks 110, 112.(Also See FIG. 7) On-board ECU 32 can modify operating parameters of theengine's fuel controller of the vehicle's ECUs 108 (see FIG. 7) throughintegration of the vehicle's electronic communication architecture 98(FIG. 7) based on the operational characteristics of the fuel combustionmap of the fuel pumped into tanks 110, 112 (discussed in detail below).The present invention 2 enables comprehensive optimization of combustionfor any and all fuel types by enabling fuel and additive producers tocreate comprehensive fuel characterization tables 210 which characterizeexactly how their products operate in specific engines. The on-board ECU32 can control a variety of fuel system components such as but notlimited to: pumps, heaters, blend valves etc. enabling modification ofthe vehicle and fuel system's standard operating conditions (discussedin detail below) to match an ideal scenario for the specified fuel'scombustion map (for example, Fuel A with additives 12, Fuel A withoutadditives 18, and Fuel B with additives 24) through integration of thevehicle's electronic communication architecture 98 based on thecomprehensive fuel characterization tables 210 of fuel pumped into tanks110,112.

Due to the variations of fuel dispensing pumps (fueling infrastructure)available at fuel dispensing systems 30, the present invention 2 willconsist of hardware and software component on the on-board ECU 32 and acompatible fuel characterization table retrofit device 40 for thefueling infrastructure's dispensing system 30. The fuel infrastructureretrofit includes a nozzle communication fob or equivalent device toinitiate and carry out communications with the fuel optimization ECU 32.A fuel system with multiple compatible fuel tanks 110, 112 can have atank identification sensor to enable ECU 32 and the fuel dispensingsystem 30 to delineate various fuels in use in multiple tanks onboardthe same vehicle. The on-board ECU 32 will communicate and detect whenthe on-vehicle tank 110, 112 is being refilled and receive comprehensivefuel characterization tables 210 transmitted by the fuel dispensingsystem's fuel characterization table retrofit device 40 as discussedabove. See FIGS. 3, 4 for details of potential flow charts for thisoperation.

Now turning to FIGS. 3 and 4 that illustrate the automatic logic andmanual process for the download of comprehensive fuel characterizationtables 210 (see FIG. 1A) onto on-board ECU 32. A fuel dispensing system30 may or may not have a fuel characterization table retrofit device 40compatible with the present invention 2. During refueling operation 300,on-board ECM 32 will recognize whether there is or is not a fuelcharacterization table retrofit device 40 unit of fuel dispensing system30. For example, one type of the vehicle sensors monitored by on-boardECU 32 are the fuel level sensors in communication with the vehicle'sfuel tank or tanks 110, 112. If the fuel characterization table retrofitdevice 40 of fuel dispensing system 30 is available 302, then on-boardECM 32 will automatically detect and initiate configuration 304 withinon-board ECU 32 of the particular fuel being dispensed in tank or tanks110, 112, based upon comprehensive fuel characterization tables 210which link the fuel combustion map files 12,18, 24 (see FIG. 1) of theparticular fuel being dispensed to the on-board ECU 32 such thaton-board ECU 32 can enable decision logic and control mechanical devicesto optimize the combustion of the vehicle's engine based upon theparticular fuel being utilized. If the compatible fuel characterizationtable retrofit device 40 of fuel dispensing system 30 is not available306, the on-board ECU 32 recognizes that there is no communication withfuel characterization table retrofit device 40. The fuel level sensorsof the vehicle in communication with on-board ECU 23 will indicate thefuel tanks are being filled 308 (fuel level sensor value has positivechange). The present invention provides at least two alternative options310, 312 to utilize the on-board ECU 32 to enable decision logic andcontrol mechanical devices to optimize the combustion of the vehicle'sengine based upon the particular fuel being utilized.

Option 1 (310): On-board ECU 32 recognizes refueling and assumes thesame fuel, as was previously used in the tank, is being utilized.Configuration parameters remain constant and monitoring occurs. Ifparameters of the comprehensive fuel characterization tables 210 such asfuel efficiency, combustion temperatures, exhaust gas temperature, fuelrail pressure etc. change by greater than a predetermined percentageduring operation, then the on-board ECU 32 generates a warningindicating the wrong fuel may be identified in the configuration ofon-board ECM 32.

Option 2 (312): On-board ECU 32 prompts the driver of vehicle to inputthe specific fuel being dispensed into tank or tanks 110, 112. Theprompt will appear on a user interface device in the vehicle eitherintegrated into the dash board signaled through the vehicle bus 162 or aseparate device 160, both in communication with on-board ECU 32.

The present invention may operate most efficiently when completerefueling is performed when switching between different types of fuelsare to be used sequentially in the same tank. For example, if a driveris to change from Fuel A to Fuel B, it is best to do so at apredetermined value, for the purposes of an example <5% fuel level willbe utilized. If the amount of Fuel A present in the tank is <5% when thetank is filled with Fuel B, this is considered to have a nominal impacton the parameters of the comprehensive fuel characterization tables 210.As discussed above and illustrated in FIGS. 3 and 4 if the amount offuel remaining in the fuel tank is >5% at the point of the refuelingoperation, on-board ECU 32 will calculate the percentages of each fuelin the tank and adjust the comprehensive fuel characterization tables210 accordingly to create mixed-fuel characterization tables. Thepredetermined value can be any value between 0% to 100% in any real orwhole number, include integers, such as a value between 0.1% and 99.9%increments of 0.1% or a value between 5% to 95% increments of 5%.

Automatic Detection and Configuration of Mixed-Fuel CharacterizationTable Example: Relating to a fuel dispensing system 30 with fuelcharacterization table retrofit device 40 and referring to FIG. 6 tank110 is filled 25% by volume with Fuel A. The remaining 75% of tank 110is filled with Fuel B during the refueling operation. On-board ECU 32adjusts fuel map characteristics to create a weighted fuel map withdistributed properties of Fuel A and Fuel B. One example of an adjustedparameter of a comprehensive mixed-fuel characterization table is themixed-fuel combustion map as determined in the process identified inFIG. 12. Due to the vast requirements of fully analyzing a variety offuels and fuel mixtures in various configurations, this data may beextrapolated initially and continually refined based upon continuedoperational feedback.

Manual Fuel Selection Ratio Example: Fuel dispensing system 30 without acompatible fuel characterization table retrofit device 40. As discussedabove, on-board ECU 32 recognizes when a tank is refilled (fuel levelsensor value has positive change), and on-board ECU 32 prompts thedriver to select the comprehensive fuel characterization table 210corresponding to the fuel added during refueling. On-board ECU 32 cancalculate the ratio based on remaining fuel prior to refueling (hereagain referring to FIG. 5, tank 110 has 25% by volume of Fuel Aremaining in the tank) and the total volume after refueling is 100%(where 75% by volume of the tank 110 is filled with Fuel B duringrefueling). On-board ECU 32 adjusts fuel map characteristics to create aweighted fuel map with the distributed properties of Fuel A and Fuel B;again as exemplified by the process identified in FIG. 12 which showscalculation of one type of adjusted parameter of a comprehensivemixed-fuel characterization table, the mixed-fuel combustion map.

Now turn to FIG. 12 for a more in-depth explanation of the modificationof one property of a comprehensive mixed-fuel characterization table,the mixed-fuel combustion map, as determined by the linear weighted fuelcombustion property process 1088. 100% Fuel A has combustion propertiesX, Y, Z, and W which correspond respectively to 100% Fuel B combustionproperties R, S, T, and U. Although one skilled in the art willrecognize there are an unlimited number of formulations that can beutilized to determine the algorithms that will create weightedmixed-fuel combustion maps, a linear correlation is utilized for thesake of clarity. If 75% by volume of Fuel B is added to tank 110 filledwith 25% by volume of Fuel A, as shown in FIG. 5, a weighted linearcalculation occurs. For example the new fuel, mixed fuel AB, hasproperties: 1) (0.25*X)+(0.75*R), 2) (0.25*Y)+(0.75*S), 3)(0.25*Z)+(0.75*T) and 4) (0.25*W)+(0.75*U) to create mixed-fuelcombustion map 1088. This process can occur in variety of locationsincluding but not limited to the on-board ECU 32 or fuelcharacterization table retrofit device 40 depending on the complexity ofthe algorithm. Once the new mixed-fuel combustion map 1088 of mixed fuelAB has been established, this information can be transmitted todatabases on the server 154 for future referencing.

Further Mixed-Fuel AB Combustion Map Example:

Fuel A, with target injection at 3° before top dead center (fuel tank110 has 25% Fuel A);

Fuel B, with target injection at 5° before top dead center (fuel tank110 has 75% Fuel B);

Weighted mixed-fuel AB target injection would be 4.5°[(0.25*3)+(0.75*5)] before top dead center (fuel tank mixed with 25%Fuel A and 75% Fuel B). The weighted mix target in this example isassumed to be a linear correlation. Other weighted mix targets can bederived based on non-linear correlations.

Now turning to FIG. 7 that illustrates diverse applications with variousfuel systems capable of being handled through the integration andcommunication of the on-board ECU 32 with the mechanical fuel systemtype 48 and fuel adjustment type 50. Examples of mechanical fuel systems48 include liquid fuels 52, compressed gas 54, liquefied gas 56, and anyother currently known or future fuel sources. Fuel adjustment type 50are possible fuel types that on-board ECU 32 can create comprehensivemixed-fuel characterization tables to adjust engine operation conditionsbased on fuel combustion and other identified properties in conjunctionwith the mechanical fuel system 48. Liquefied fuels 52 can be a mixtureof diesel compatible fuels 58 and gasoline compatible fuels 60, wherediesel compatible fuels 59 can include diesel with additives 72,biofuels 74, aviation fuels 76, and miscellaneous fuels 78 determined bythe fuel company. Biofuels 74 can include biodiesel 84, vegetable oils86, algae oils 88, and synthetic fuels 90. Gasoline compatible fuels 60can include fuel additives 80 and ethanol 82. Ethanol fuel 82 caninclude corn-based fuel 92 and cellulosic fuel 94. Compressed gas 54 caninclude natural gas 62, propane 64, and proprietary blends 66. Liquefiedgas 56 can include liquefied natural gas (LNG) 68 and propane 70.

Now returning to FIG. 7 for an illustration of an exemplary integrationof on-board ECU 32 of present invention 2 incorporated into a vehicle'srenewable fuel system 156 and electronic architecture 98 along with thecommunication network and server 154 linking the on-board ECU 32 withclient interfaces 100 and present invention management interface 102.For this detailed example, a diesel engine will be used for illustrationpurposes and it is not intended to limit the present invention to onlydiesel engine applications. The present invention 2 includes theintegration of a traditional fuel system (such as a diesel system) withan alternative fuel system (such as a biodiesel fuel system) into oneintegral multi-fuel system 156. As mentioned above, the presentinvention 2 can include an on-board ECU 32 installed in a vehicle incommunication with the vehicle ECUs 108 to monitor a number of standardengine and system parameters that adapts the renewable fuel system 156state accordingly, which is the collection of mechanical componentsinteracting with the On-board ECU 32. One embodiment of a renewable fuelsystem 156 can include a heated or cooled auxiliary fuel tank 110, aheated or cooled diesel or traditional fuel tank 112, pre-filter/checkvalves 114A, 114B, mixing valve 116, pump 118, micronic filtration 120and fuel selector valves 126. The system is fluidly connected to engine130 by renewable fuel system fuel lines 132, diesel fuel supply line 136and common fuel lines 134. The heated or cooled fuel tanks 110, 112provide a means to adjust the viscosity of the fuel in either tanks toaccommodate ambient conditions and to facilitate optimal fuel blend maps212, 214, 216 that correspond with fuel combustion maps 10 based oncomprehensive fuel characterization tables 210 (FIGS. 1, 1A) discussedabove. The return fuel selector valve 126 b has an input line 138returning fuel from engine 130 and output lines 142, 144 to directengine returning fuel to the diesel tank 112 or fuel feed point 146,respectively. Renewable fuel system 156 can also include an air bleedreturn line 148 from micronic filtration 120 to fuel tank 110.

A further aspect of present invention 2 is communication of systeminformation to a remote server 154 via any number of wired or wirelesstransmission methods 150, 152 via connection 162. This communicationenables view and control of functions and data from the on-board ECU 32by client interface 100 and the management interface 102. The managementinterface 102 can maintain all collected data and system parameters inthe system server 154 and provide access to this information to theclient interface 100 for use by technicians (performing service,configuration, etc.),fleet managers (for data collection and analysis),fuel producers (for continued refinement of fuel combustion mapproperties) and others as needed for business and research activities.Application pages can include: Vehicle data download to database;charting; ECU configuration; Control/Setup mode; Real-time display ofinformation; and on-board ECU software/system updates.

As discussed above, a basic function of the present invention 2 is tooptimize a renewable fuel blend. This can be done in any number of ways.One example is by adjusting the viscosity of the alternative fuel 106.One embodiment of the on-board ECU 32 of the present invention 2monitors system parameters of the renewable fuel system 156 includingthe temperature of the fuels in tanks 110, 112 to activate heaters orcoolers in tanks 110, 112 to mechanically adjust the viscosity of thefuels to meet parameters of the optimum combustion characteristics asdefined by the fuel combustion maps 12, 18, 24. For example, thealternative fuel 106 in auxiliary tank 110 can be heated based on theparameters identified in the comprehensive fuel characterization tables210 (see FIG. 1A) in the on-board ECU 32 to reduce the alternative fuelviscosity to the level of the traditional fuel designed for used in thevehicle, such that the spray pattern of traditional fuel (for example,petroleum diesel) is replicated by the alternative fuel 106 (forexample, bio-diesel) during injection enabling the best emissions andperformance of the engine. Additionally, another method for viscosityadjustment includes the traditional or diesel fuel 104 in tank 112 beblended into the renewable fuel at blending valve 116 based on fuelblend maps 212, 214, 216 in the comprehensive fuel characterizationtables 210 and on-board ECU 32. Blending to reduce the alternativefuel's viscosity to accommodate current operating conditions enableson-board ECU 32 to optimize fuel usage based on the fuel blend maps 212,214, 216 which adjust the viscosity of the fuel based on temperature andblend percent of fuel. Fuel blend maps 212, 214, 216 allow forcalculation of the optimal fuel blend and enable the engine to utilizethe greatest renewable fuel concentration possible for the real-timeoperating conditions.

FIGS. 13 and 14 show variations of this embodiment utilizing 100%biodiesel (B100) and waste vegetable oil (WVO). These fuels have varyingviscosities based upon temperature and amount of traditional dieselblended into the fuel. The present invention allows blending valve 116to mix fuel from the renewable fuel tank 110 with fuel in thetraditional diesel tank 112. One example would be to seek a targetviscosity of 2-4 cSt (viscosity of traditional diesel at 40 C). Oneembodiment of renewable fuel system 156 blending WVO with diesel toreach a homogenous mixture with a viscosity of approximately 4 cSt at 40degrees C. utilizes fuel blend maps 212, 214, 216 for calculation ofblend percentage. One example of the WVO/diesel fuel blend mapcharacteristics are identified in FIG. 14. At 40 C WVO can be suitablymixed into diesel in concentrations up to 18% (82% diesel). This blendedfuel, in turn, matches the target viscosity identified (4 cSt) and byresult has suitable fuel transfer properties, a similar atomizationspray pattern from injectors and can more completely achieve injectioncharacteristics as identified by fuel combustion maps 12, 18, 24. Nowturning to FIG. 13, the upper limit of B100 concentration (to achieve atarget viscosity of 4 cSt at 40 C) mixed into diesel is approximately70% (30% diesel). Maximum blend configurations for utilization in fuelblend maps 212, 214, 216 are determined for all operational temperatureranges (40 C has been selected as one example of a complete profile).One skilled in the art will recognize additional properties can beanalyzed to derive a more robust fuel blend map.

One example of operation of the system implementing blending valve 116functionality is: as the engine 130 warms up on a summer day, it may beoperating on a 60% biofuel blend as determined by fuel blend maps 212,214, 216, where the same engine 130 and fuel combination will operate ona 25% blend on a winter day based on the same fuel blend maps 212, 214,216. The on-board ECU 32 can also adjust for barometric pressure,humidity, and load conditions. All of these factors can affect theperformance, combustion and emissions of the engine and are collectivelyrepresented by the comprehensive fuel characterization tables 210. Theon-board ECU 32 processes inputs from the Vehicle's ECU 108 and therenewable fuel system 156 in real time to determine on asecond-by-second basis the appropriate blend of non-traditional oralternative fuel (for example, biofuel) as identified by fuel blend maps212, 214, 216. The on-board ECU 32 in communication with the vehicle'sECU 108 adjusts parameters based upon the most current fuel combustionmap in the comprehensive fuel characterization tables 210 as providedduring refueling through fuel characterization table retrofit device 40.This enables functional adjustments of the timing, injection, exhaustgas recirculation and a plethora of other engine parameters of engine130 to optimize the combustion of biofuel. This optimization can occurin a variety of ways. Two examples are that the vehicle ECU signals fromthe vehicle ECUs 108 can be redirected through the on-board ECU 32 formodification and transmission from on-board ECU 32 or the onboard ECU 32can overwrite/reflash the engine's ECU 108 so that the optimized signalsare embedded within and sent from the original ECUs 108 rather thanbeing routed through ECU 32.

As discussed above, the on-board ECU 32 can detect the type of fuelbeing utilized thorough fuel characterization table retrofit device 40.Algae Oil, Soybean Oil, Animal Fat based Biodiesel or any other fuelthat can defined and programmed into the on-board ECU 32 and fuelcombustion maps 12, 18, 24 (or engine parameters) can be optimized bythe present invention. Each of these fuels has unique combustionproperties, identified in fuel combustion maps 12, 18, 24, that therenewable fuel system 156 can accommodate and optimize in real time.

The on-board ECU 32 receives real time dynamic feedback (e.g., ambientand engine conditions) from vehicle ECUs 108 and blends the alternativefuel 106 in auxiliary tank 110 with traditional fuel 104 in traditionalfuel tank 112 (such as diesel fuel) in a range of 0-100%. This blendratio is adjusted at blend valve 116 based on upon predetermined fuelblend maps 212, 214, 216 (see FIG. 1A) programmed into the software ofon-board ECU 32. These fuel blend maps 212, 214, 216 can be optimizedbased upon the specific properties of the alternative fuel 106. SeeFIGS. 13, 14 for examples of calculating fuel blend maps 212, 214, 216based on varying viscosities as determined by temperature and amount oftraditional diesel blended into the fuel.

System Terms:

Fuel Combustion Map—Engine specific combustion parameters based uponpredetermined fuel specific combustion parameters

Fuel Emissions Profile—Engine specific emission parameters based uponfuel specific operational parameters

Fuel Blend Map—Fuel specific parameters based upon temperature,viscosity and other parameters of varying blend percentages of two ormore fuels

Comprehensive Fuel Characterization Table—A compilation of FuelCombustion Maps, Fuel Emissions Profiles, Fuel Blend Maps and otherquantified parameters of a specific fuel

Fuel Flow Rate Sensors (not shown)—These sensors monitor the fuel flowrate of the system. One sensor is located in the fuel supply (tankoutlets 168, 170) and one sensor is located in the fuel return outlets172, 174; this gives the system the ability to calculate fuel flow andconsumption.

EGT Sensor (not shown)—The Exhaust Gas Temperature (EGT) sensor is apyrometer located in the engine's exhaust manifold (not shown) todetermine the temperature of combustion. There is one EGT sensor in themain system and an auxiliary module with EGT sensors for each individualcylinder from 1-12.

Temperature Sensors (not shown)—The heart of the blending valve systemoperation is based upon fuel viscosity and thus temperature. Temperaturesensors can be placed in various points throughout the fuel system toaccurately monitor the fuel temperature of the system. (e.g. fuel tank,fuel lines, blending valves, filter, engine input, engine output).

Fuel Selector Valves 126—These valves are on/off valves that determinesupply and return status of the fuel system.

Blending Valve 116—This valve is a valve that blends diesel and biofuel.

Fuel Level sensor (not shown)—The fuel level sensors monitors fuellevels of both the diesel and biofuel tank.

As mentioned above, on-board ECU 32 can monitor and control an engine'scombustion parameters and the operational characteristics of the primaryfuel system (such as traditional fuel tank 112 and up-stream anddown-stream components of engine 130) and a secondary fuel system (suchas auxiliary fuel tank 110 and up-stream and down-stream components ofengine 130).

In operation, it is undesirable with various biofuels to utilizebiofuels in an engine before it has come to operational temperature.During “cold” operation, the piston rings are not fully expanded(sealed). During startup and “cold” operation, fuel bypasses the ringsand is deposited in small concentrations in the crankcase oil. Withtraditional petroleum distillates, this is not a significant issue, asthey will evaporate during operation. With some biofuels, evaporationfrom the crankcase oil does not occur as readily and the result is abuildup of biofuel concentration in the crankcase oil. Havingsignificantly different properties than the petroleum distillates, thebiofuels tend to polymerize under the conditions the crankcase oil issubjected to. This polymerization can lead to catastrophic enginefailure as the crankcase oil begins to degrade and polymerize as aresult of this reaction. To minimize crankcase oil fuel contamination,on-board ECU 32 accommodates for start-up offsets as identified byparameters in the comprehensive fuel characterization tables 210—theengine will begin to operate on traditional fuel until the desiredoperating parameters are met. Once the engine has come to operatingtemperature, the piston rings are sufficiently sealed and thepossibility for fuel to bypass the rings is significantly minimized,on-board ECU 32 will switch to biofuel usage.

In addition to the above mentioned features, the present invention 2 hasa user interface 160 in communication with on-board ECU 32 viaconnection 178 that will enable real time transmission of feedback andsystem performance to the driver. This is specifically valuable as itpertains to driver operation. The system is able to calculate real timeefficiency and provide this information back to the driver; the systemalso provides a variety of other feedback to optimize efficient drivingbehavior such as warnings for hard braking, acceleration and cornering.As an example: Referring to FIG. 8 for an illustration, fuel A's fuelcombustion map 1084 (FIG. 12) identifies that fuel A operates mostefficiently at 3500 RPMs where Fuel B's fuel combustion map 1086 (FIG.12) identifies that fuel B operates most efficiently at a higher 4500RPMs. The differences here may be only the addition of a fuel additiveor these may be two completely different fuels (e.g., Diesel andBiodiesel). The present invention 2 characterizes the fuel to enable thesystem to provide feedback to the driver based on the desired operatingparameters of the specific fuel. These fuels as identified by fuel A1048 and fuel B 1050 when mixed at a 50-50 ratio into fuel tank 1046.The optimizing ECU 32 recognizes the fuels and their associatedparameters from the comprehensive mixed-fuel characterization tables 210and gives feedback via User Interface 160 to suggest the driver maintainoperation in a range of 4000 RPMs 1052 (average of 3500 and 4500 RPMs).

Now returning to FIG. 7, on-board ECU 32 communicates with bus system162 in addition to renewable fuel system 156. The basic theory ofoperation is that the vehicle will start on diesel (or other traditionalfuel) and run until the operating parameters are met, at which pointon-board ECU 32 engages renewable fuel system 156. Upon engine shutdown,if the engine 130 is still operating on the renewable fuel system 156,on-board ECU 32 will engage a purge cycle to clear out the engine andinjectors of alternative fuel 106. Purge cycles are determined at thetime of installation and are engine specific.

Vehicle ECUs 108 represents any electronic control unit tied into theVehicle's Bus system 162. The Vehicle Bus 162 is an internalcommunication network that has been created to tolerate conditions foundin vehicles. The vehicle bus system 162, or central network,interconnects multiple ECU modules 108 inside a vehicle with each ECUspecific mechanical components related to its function. Once connectedto the vehicle bus system 162, the vehicle ECU modules 108 cancommunicate with other modules as necessary using a standard protocol.

There are several different vehicle bus protocols:

J1939 is a standard that is an adaptation of CAN for agricultural andcommercial vehicles. CAN (controller area network) is a message basedprotocol originally designed to interconnect automotive components butis now also found in other applications such as marine propulsion andpower generation. OBDII standard specifies the properties of the OBDIIconnector as well as a messaging format (OBDII protocol) for gainingaccess to vehicle information.

The OBDII protocol provides a messaging format for requesting data fromthe vehicle ECU modules 108. It provides a list of potential parameterswhich could be monitored along with how to encode data for each. Thegeneral protocol defines a base group of engine sensors and parametersthat have “open access.” Manufactures may extend the list to includeproprietary parameter data. The standard also provides an extensiblelist of Diagnostic Trouble Codes (DTC).

The on-board ECU 32 can utilize a standard J1939/OBDII→USB cable 164 toconnect the Technician Computer 158 to the Vehicle Bus system 162 toaccess and modify the on-board ECU 32. For an isolated operation mode,the on-board ECU 32 can be linked directly to the Technician Computer158 via a cable 165.

Operational Modes of the On-Board ECU 32

There are two main and two sub-operation modes. The two main operatingmodes are Isolated and ECU Linked, and the two sub-operating modes ofthe controller are Static and Dynamic. In ECU Linked mode, the On-boardECU 32 will communicate with the vehicle ECUs 108. In the Isolated mode,the On-board ECU 32 operates independently of the engines systemsVEHICLE ECUs 108 with no conditions for outside variables. In staticmode, the biofuel system provides a single fuel. In dynamic mode, thebiofuel system can mix at any blend to achieve optimal performance asdetermined by fuel blend maps 212, 214, 216. For example:

Isolated—Static Mode: On-board ECU 32 reads in all sensors in renewablefuel system 156 and utilizes on/off fuel selector valves 126A to switchbetween blended fuel and 100% diesel fuel. This is typically utilizedwhen implementing the system is a non-electronically controlled engine(e.g., no vehicle ECUs 108) for use with multiple fuels.

Isolated—Dynamic Mode: On-board ECU 32 reads in all sensors in renewablefuel system 156 and utilizes blending fuel valves 116 to optimize thefuel blend. This mode is designed to optimize fuel use based solely onbasic fuel properties and does not optimize engine performance based onknown fuel combustion maps 12, 18, 24.

ECU Linked—Static Mode: This is utilized for modern electroniccontrolled engines (e.g., with vehicle ECUs 108) and is linked to thevehicles CAN network such as J1939, J1708, OBDII or other systems toextract, transmit and monitor data collected and stored in vehicle ECUs108. This data will be utilized in the system's decision-making logic ofOn-board ECU 32 to activate on/off fuel selector valves 126A to switchbetween blended fuel and 100% diesel fuel.

The on-board ECU 32 also can detect when a Diesel Particulate Filter 131equipped engine engages the “regeneration” cycle and will default thesystem back to traditional diesel. A Diesel Particulate Filter (DPF) 131(FIG. 7) is connected to the tailpipe of a diesel vehicle andmechanically filters particulates from tailpipe emissions. At variedintervals, the DPF 131 will become clogged with particulate matter andengage in a “regeneration” cycle which utilizes fuel to increase theexhaust temperature and burn off the clogged particulates. Similar tothe start-up offsets, there is preliminary speculation that a DieselParticulate Filter's 131 regeneration cycle is not optimally designedfor use with nontraditional fuels. The on-board ECU 32 enables thepresent invention 2 to disengage the nontraditional or alternative fuelduring a regeneration cycle to optimize its effectiveness and thenreengage once normal operation resumes. See FIG. 9 for an illustrationof this embodiment for an engine adapted with a two tank renewable fuelsystem such as the one depicted in FIG. 7. The engine 130 is operatingon up to 100% blend of biofuel in Tank 110 depicted in 1054. The DPF 131sensor data is communicated to the Vehicle Bus 162 which is monitoredthe Optimizing ECU 32 through operation 1056. If DPF regeneration is notoccurring, the system continues on “normal” operation. If DPFregeneration mode begins 1058, the fuel mix is switched to diesel onlyfuel in tank 104 and the system operates on the traditional dieselsystem until the regeneration mode is completed 1066 at which point thesystem resumes normal operation 1054.

ECU Linked—Dynamic Mode: This is the ideal and optimal operational modeof the present invention 2. In dynamic mode, the On-board ECU 32controls a variety of electronic and mechanical controls to achieve theabsolutely optimal conditions for combustion (discussed in more detailbelow). The on-board ECU 32 controls fuel blending valve 116 to blendfuel or additives in any percentage to achieve the ideal result asdetermined by comprehensive fuel characterization tables 210 (See FIG.1A). One embodiment of additive blending is shown in FIG. 10. Oneembodiment of the system enables additives to be blended into fuel(diesel, natural gas, etc.) from 0% to 99% utilizing pre-filter/checkvalves 114 A,B and mixing valve 116 as determined by comprehensive fuelcharacterization tables 210.

Another embodiment of the present invention includes a Technician Mode.This is an external computer interface 164 that enables a technician toprogram, extract data, log maintenance and troubleshoot systemperformance.

Another embodiment of the present invention includes Remote FirmwareUpgrade. System management 102 enables software updates to the on-boardECU 32 via wireless connection 150 or cellular connection 152.

Another embodiment of the present invention includes GPS. Mapping andnavigation software can be embedded into the on-board ECU 32 and linkedto an embedded database of alternative fueling stations to give accessto a variety of fuels when available. This feature can be linked to thefueling stations utilizing the fuel characterization table retrofitdevice 40 to self-populate and identify exactly what type of fuel isavailable.

All system data is accessible for monitoring and troubleshooting inreal-time by plugging a user interface 160 (such as a laptop) into theon-board ECU 32. This data can be viewed in the form of numerical data,graphical representation, a cockpit simulation or any split screencombination.

In response to a fault condition or system shutdown the renewable fuelsystem 156 will run a purge cycle. During the purge cycle, renewablefuel system 156 will switch back to diesel operation and clear the lines132 of biofuel. There are two types of purge cycles Idle andOperational. At idle the engine 130 consumes much less fuel than whenthe system is operating. The purge timing for Idle purge will be set atinstallation, if the purge is engaged when the engine 130 is operatingwithin 10% of the engine idle, vehicle ECUs 108 will send a signal toon-board ECU 32 and on-board ECU 32 will control the fuel valves 126A,126B to start the Idle purge. If the engine 130 is not within idleparameters, vehicle ECUs 108 will send a signal to on-board ECU 32 andon-board ECU 32 will start the Operational purge. The Operational purgeutilizes a shorter, compensated purge time depending upon the engineload and determined based upon an engine specific load vs. purge timetable one example is illustrated in FIG. 15. In ECU Linked systems, theextended purge cycle will raise engine idle a programmable amount (forexample between 2-5 times that of idle) to ensure complete eliminationof biofuel from the injectors.

The present invention can respond to fault conditions including but notlimited to the following faults:

If the renewable fuel system 156 fuel temperature drops below the presetacceptable temperature, and therefore is outside of the define fuelblend maps 212, 214, 216, the on-board ECU 32 will initiate a purgecycle.

If the exhaust gas temperature drops below the preset acceptabletemperature, the on-board ECU 32 will initiate a purge cycle.

If the biofuel level drops below the preset acceptable level, theon-board ECU 32 will initiate a purge cycle.

When the engine 130 is at idle for the preset amount of time, theon-board ECU 32 will initiate a purge cycle. The on-board ECU 32 willraise the engine load prior to initiating a purge to extend the time ofoperation on biofuel.

If the engine 130 initiates a Diesel Particulate Filter (DPF) 131regeneration, the on-board ECU 32 will initiate a purge as illustratedin FIG. 9.

Gallons Displaced Web App—The Optimizing ECU 32 can have the ability toidentify the fuel being used by data in the comprehensive fuelcharacterization tables 210 and track the amount consumed 1076. Forexample, total Biofuel consumed will be logged by the on-board ECU 32,as this information is downloaded to the Management Server 154 andClient Application, this data will be accessible to a “counter” on theclient's website. As biofuel consumption numbers increase this will showusers at the clients' websites their petroleum mitigation and emissionreduction statistics.

This feature can also be linked to carbon mitigation metrics for use incarbon aggregation projects and for salable carbon credit programs. Eachfuels' emissions properties are loaded onto the optimizing ECU 32 aspart of the fuel emission profiles 224 in the comprehensive fuelcharacterization tables 210. As emission standards become stricter,tracking of engine specific emission sources will become increasinglycritical. By tracking the real-time fuel combustion maps 12, 18, 24 andcorrelating these with the fuel consumed, emission performancecharacteristics from fuel emission profiles 224, overall emissionreductions can be interpolated and recorded. Emission reductions, suchas carbon, may have value on a salable market. This information istransmitted to a remote server 154 and uniquely serialized. Theseuniquely identified emissions are then aggregated in various forms andmay be presented to market for sale. Once these offsets have beenpurchased the unique serial numbers are identified as utilized and areno longer salable. FIG. 11 illustrates one example of this embodiment.

To summarize, the overall goal of the system is to characterize theoptimal fuel combustion and efficiency characteristics of a fuel and thedriver behavior. In one embodiment of the present invention 2, thisinformation is embedded into the fuel characterization table retrofitdevice 40 at the fueling infrastructure and transmitted to the on-boardECU 32 during refueling. With this information and the identification ofthe specific engine that is being refueled, on-board ECU 32 cancalculate and utilize the optimal engine timing and operationalparameters, as identified incomprehensive fuel characterization tables210 discussed above. In addition, through the user interface 160,on-board ECU 32 can provide real time feedback to the driver to ensurethat these efficiencies are being maximized to the fullest extentpossible. The data logging and connectivity of the system to a centralserver 154 enables constant improvement of the operating characteristicsthrough comprehensive fuel characterization tables 210 based upon realoperational scenarios and also provides fleet managers the ability tomonitor, track and rate the performance of various fuels, engines anddrivers.

Although the present invention has generally been described in terms ofspecific embodiments and implementations, the present invention isapplicable to other methods, apparatuses, systems, and technologies. Theexamples provided herein are illustrative and not limiting, and othervariations and modifications of the present invention are contemplated.Those and other variations and modifications of the present inventionare possible and contemplated, and it is intended that the foregoingspecification and the following claims cover such modifications andvariations.

I claim:
 1. A method to blend fuels comprising the steps of: providing a vehicle with two fuel tanks and an on-board electronic control unit having a processor, a database, wherein fuel combustion maps for fuels in the two fuel tanks are stored on the database, wherein each fuel tank is in communication with a fuel system of the vehicle; determining portions of each the two fuels for a blended fuel map; mixing the portions of the two fuels to create the blended fuel; and creating a unique blended fuel combustion map of the blended fuel based on the fuel combustion maps of the two fuels, wherein the original equipment manufacturer vehicle electronic control unit utilizes the unique fuel combustion map to operate the engine.
 2. The method according to claim 1, further comprising the step of adjusting viscosity of one or both of the two fuels to the level of a fuel for which the engine was designed for prior to the step of mixing.
 3. The method according to claim 2, wherein the step of adjusting viscosity comprising the step of thermal adjustment of one or both the two fuels.
 4. The method according to claim 2, wherein the step of adjusting viscosity comprising the step of blending the two fuels based on specific fuel blend maps located within comprehensive fuel characterization tables.
 5. The method according to claim 1, further comprising the step of providing real-time feedback to a driver the optimal vehicle operating conditions associated with the blended fuel.
 6. The method according to claim 1, wherein one fuel of the two fuels is diesel and the other fuel of the two fuels is an alternative fuel, and further comprising the step of detecting when a diesel particulate filter equipped engine engages a regeneration cycle and defaulting the fuel system to use only the diesel fuel. 